A large number of solid agents used in cosmetic compositions, for example, often have low solubilities in solvents or liquid agents, and thus a tendency to recrystallize rapidly within the compositions. Recrystallization of solid cosmetic agents, not only negatively impacts the performance of the cosmetic composition but also can result in a grainy composition having inferior sensory attributes.
With sunscreens, for example, in order to achieve good protection, excessively large proportions of oily solvents are often needed to enhance solubility of the sunscreen. This approach, however, invariably yields a final cosmetic composition that delivers an oily or greasy feel that is not typically enjoyed by consumers.
Another technique employed to prevent solid agent recrystallization in compositions is encapsulation. Encapsulation, nevertheless, can be expensive and prevents solubilization of solid agent within a composition (like a cosmetic composition). As a result of this, it is often observed that less agent (e.g., active) is delivered through skin when the same is encapsulated and applied topically.
There is an increasing interest to develop cosmetic compositions for topical application that minimize recrystallization in the absence of encapsulation. Moreover, there is an increasing interest to enhance solubility of solid agents within compositions so that a maximum amount of such agents may be delivered topically to consumers from cosmetic compositions. This invention, therefore, is directed to stabilized cosmetic compositions that comprise a tricyclodecane amide. The tricyclodecane amide unexpectedly enhances solubility of solid agents in liquid agents within the compositions. The enhancement of solid agent solubility is surprisingly achieved while simultaneously delivering compositions that yield excellent sensory benefits upon topical application. Although not wishing to be bound by this theory, it is believed that tricyclodecane amides have a unique cage structure, which renders them small and bulky, therefore allowing them to disturb the ordered packing and formation or growth of crystals. Also as part of the present invention it has been discovered that tricyclodecane amides themselves have cosmetic benefits, such as sebum suppression and boosting UV-A, UV-B, and SPF performance of common sunscreen agents.
Additional Information
Efforts have been disclosed for increasing the solubility of benefit agents within a cosmetic composition. In United States Patent Application No. 2006/0024337 A1, a process is described for dissolving lipophilic compounds with amphiphilic block copolymers in cosmetic compositions. Other efforts have been described for enhancing benefit agent deposition within personal wash compositions. In U.S. Pat. No. 6,576,228 B1, personal wash compositions with water-soluble compounds for providing enhanced SPF are described. Still other efforts have been disclosed for enhancing benefit agent deposition. In U.S. Pat. No. 6,399,045 B1, liquid personal wash compositions with benefit agent and cationic polymers are described.
Tricyclodecane derivatives, and in some cases tricyclodecane amides, have been described. See for instance Kilburn et al., U.S. Pat. No. 8,053,431B2; W02004/089415A2 (Novo Nordisk NS); W02004/089416A2 (Novo Nordisk NS); Narula et al., U.S. Pat. No. 4,985,403; Mathonneau, US 2006057083; WO06/119283 (Hunton & Williams LLP); WO08/054144 (Amorepacific Corporation).